Switch mechanism



July 18. 1944. H. PpRAT-W v 2,353,347

SWITCH MEGBANISM originar Filed Aug. 2, 1940 ATTORNEYIff Patented July 18, 1944 SWITCH MECHANISM Hugo Purat, Detroit, Mich., assigner to Progressive Welder Company, Detroit, Mich., a corporation kof Michigan original application August '2, 1940, seria1`1N0.,

349,653. Divided and this application October 15,1942, vserial No. 462,452

(Cl. o-165) 5 Claims.

The present invention relates to switch mechanisms well adapted for but not limited to use in electric welding machines. The present application is a division of applicantsA copending application Serial No. 349,653, filed August 2, 1940.

The principal objects of the present invention are to provide a switch mechanism which is economical of manufacture and assembly and which is reliable and ei'lcient in operation; to provide such a structure embodying relatively Xed and movable contact elements and further embodying means to provide an efiicient contact pressure therebetween; to provide such a construction employing a pair of relatively fixed contact surfaces and a bridge member, the parts being arranged .so that when the bridge member is actuated to electrically connect the first surfaces, it is forced into firm contact therewith.

With the above as well as other objects in view, which appear in the following description and in the appended claims, a preferred but illustrative embodiment of the invention is shown in the accompanying drawing, in which the sole ligure is a view in longitudinal contral section of a switch embodying the invention and also to a resiliently mounted but movable electrode 36, which may be associated with, for example, a cooperating fixed electrode (not shown). The electrode 36 may be carried by a movable carriage 24, and it will be appreciated that when the carriage V24V is elevated, the movable electrode 36 is positioned in spaced relation to the cooperating stationary electrode. When the carriage 24 is moved downwardly to welding position, the work is clamped between the stationary and movable electrodes.

In further accordance with the arrangement disclosed in the above-identified copending application, the movable electrode 36 is resiliently supported, so as to enable it to yieldingly engage the work to be welded. More particularly the movable electrode 36 is secured in a block 42, which block is attached to, but insulated from, a rod 44, by means of a sleeve 46. Each rod 44 is slidably supported, for limited vertical movement, in a pair of threaded sleeves 48 and 50, which sleeves are mounted in the flanges of a channel-shaped bar 52, xedly secured to the carriage 24. The rod 44, and consequently the electrode 36, is continuously urged downwardly relative to the bar 52 by means of a compression Aments of the carriage 24.

spring 5B, one end whereoibears against the sleeve 48, and the other end whereof bears against a washer, which seatsy againstl a shoulder formed on the rod. The spring 56 is enclosed within a pair of telescoping shells 6| and 62. It will be observed that the sleeve 5l), against which the washer 58 bears, determines the limit of .downward movement Vimparted to the rod 44 by the spring 56, whereas the sleeve 48 affords an adjustment of the spring 56, so as to vary its tension and consequently Vary the pressure eX- erted between the stationary electrode 30 and a cooperating movable electrode 36. K

The electrode supporting block 42 is permanently electrically connected, by means of a flexible lead, such as the lead l0, to the present improved'switch 12. The electrode switch '|2 comprises a cylindrical body 14, formed of conducting material, and permanently connected to Vthe associated lead 'IU by means of a connecting block '|6. Also, the switch body is permanently connected to, but insulated from, a supply bus bar 18, 'by means of studs 86 and insulating gaskets 82. The bus bar 18 is carried by a support 84, lxedly supported at its'ends inthe movable carriage 24. The bus bar i8 may also be permanently electrically connected to one terminal of the associated 'current' source (not shown) in any suitable manner',` as by a` flexible lead which accommodates the vertical move- The 'fixed electrode (not shown) may be permanently connected to the other terminal kof the source.

The switch 'l2 comprises a stationary contact member 9|) having an angled upper surface 9| for cooperation with the correspondingly angled lower surface 93 of a cooperating contact member 92. The contact member 96 is wedged in a tapered bore formed in the bus bar 'I8 and thus is stationary. The contact member 92 is vertically slidable within `the bore formed in the switch body 14 and is normally retained in the illustrated upper position in which the angled surfaces are separated, by means of a compression spring |96. 'I'he compression spring |06 is seated in a counterbore formed in the switch body and the upper end thereof bears against the under side of a collar 94. The collar 94 is connected to the Contact 92 by means of a headed stud |08.

The solenoid structure for closing the switch 12 comprises a coil |90, which is supported upon a core piece |04. The coil IDB is enclosed by means of a shell |02 and a cover plate IUI, which elements, it will be appreciated, are formed of magnetic material and thus constitute a part of the magnetic circuit, of the solenoid. The armature structure for the solenoid comprises the cylindrical member 98, which receives a. threaded adjusting screw 99, the lower end of which adjusting screw bears against the headed member |01. The member |01 is loosely received in the bore of the core piece |04, and downward force applied to the member |01 is transmitted to the collar 94 through a washer |03 and a compressible cushion` 96. The upper end of the member |01 is received in the bore provided in the armature member 98," and thus serves to guide said armature member.

' wardly into wedging engagement with the contact 90. This wedging movement causes the surfaces` 9| and 93 to wipe acrosseach other and in accordance with the disclosure of Patent No.

2,126,490, this action wedges the contact 92 into lateral engagement with the bore of .the switch body 14. An eicient electrical connection is thus made, through the contacts 90 and 92, between the bus bar 18 and the associated movable electrode 36.

It is desirable to enablethe armature member 98 to move downwardly far enough to engage the core piece |04, thus closing the previously mentioned air gap, and it will be appreciated that the compressible member 96 is proportioned to accommodate such nal movement of the armature member 98.

Although only a single complete embodiment of the invention has been described in detail, it will be appreciated that various modifications in the form, number and arrangement of parts may be made within the spirit and scope thereof.

ytion and a projected position in which it engages the cooperating member, and operating means for the contact member including means to cause it to solidly bear against the sidewall of the bore when it engages 4the cooperating memberV to thereby electrically connect said bore and said cooperating member.

2. A switch comprising a supporting member having a bore, a cooperating member electrically separate from said bore, a contact member movable in the bore between a retracted position and a circuit closing position in which it engages the cooperating member, and means for moving the contact member to the circuit closing position,

said cooperating member and said contact member cooperating when the contact member is in the circuit closing position to cause said contact member to solidly bear against the wall of the .bore to thereby electrically connect said bore and said cooperating member.

3. A switch comprising a supporting member 7, havingja bore, a cooperating member electrically separate from said bore, a contact member movable in the bore between a retracted position and acircuitclosing position in which it engages the cooperating member, and means for moving the contact member to the circuit closing position, said cooperating member and contact member lhaving mated tapered faces which act when pressure is applied yto the contact member to cause the contact member to solidly bear against `the wall of the bore to thereby electrically connect said bore and said cooperating member.

4. In a switch, the combination of a supporting member having a contact surface, a cooperating member electrically separate from said surface, a contact member movable along said surface from a retracted position to a circuit closing position in which it engages said cooperating member, said switch including means for moving saidcontact member to the circuit closing position and for causing it when so moved to solidly bear against said contact surface to thereby electrically connect said surface and said cooperating member.

5. In a switch, the combination of a supporting member having a contact surface, a cooperating member electrically separate from said surface, a contact member movable along said surface from a retracted position to a :circuit closing position in which it engages said cooperating member, and means for moving said contact member to the circuit closing position, said cooperating member and contact member having mated tapered faces which act when pressure is applied to the contact member to cause the contact member to solidly bear against said surface to thereby electrically connect said surface and said cooperating member.

' HUGO PURAT. 

